Variable-stroke pump.



C. IVI. MANLY..

VARIABLE STROKE PUMP.

APPLlcATloN FILED APR.24. 1913.

Patented May 22, 1917.

3 s HEETs-SHEET 1.

@mi btw ooe@ t C. IVIy MANLY. VARIABLE s TRoKE PUMP. APPLICATION FILED APR. 24. 1913.

Patented May 22,1917.

3 SHEETS-SHEET 2.

C. IVI. MANLY.

VARIABLE STROKE PUMP.

APPLICATION FILED AI=I1.24. Isla.

Patented May 22,1917.

3 SHEETS-SHEET 3.

` `3 mm nto/r, @M 2^ M e1! Homan, 771 l UNrrED sirA'rEs PATaNT OFFICE.

CHARLS M. MANLY, F FREEPORT, NEW YORK.

VARIABLE-STROKE PUMP.

[o all whom it may concern.'

Be it known that I, CHARLES MATTHEWS MANLY, a citizen of the United States, and a resident of the village .of Freeport, inthe county of Nassau and State of New York,

` have invented a certain new and useful Improvement in Variable-Stroke Pumps, of which the :following vis a specification.

This invention relates to` variable stroke pumps and particularly to pumps of that vcharacter which are especially designed for use as the ldriving element of a variable speed hydraulic power transmission mechanism. One type of such mechanisms which at this time are beginning to come into use is' shown in my prior Patent No. 801,097 of ible degrees from a maximum capacity flowing in lone direction around the circuit through zero to a maximum capacity flowing in the opposite direction. My present invention relates more particularly to such variable stroke crank shaft and the means for adjusting it, the other parts of the mechanism being .in essential particulars the same as that disclosed in my prior patent above referred to.

The objects of my present invention are to provide a crank shaft of this type composed of aminimum number of parts and having a power operated adjusting mechanism which is simple and positive in its action and exerts no reaction on the hand` of the operator. Y

A further object of the vinvention is to provide a crank shaft of the type specied in which the centrifugal forces -of `its component parts are balanced relative to the A center of rotation in all positions of adjustment. Further objects ofthe invention are to generally improve the construction of a crank shaft of this type and its coperaty ing parts as will hereinafter appear.

In the accompanying drawings there is illustrated a preferred embodiment of my improved variable capacity pump, and it is Specification of Letters Patent.

Patented May 22, 1917.

Application led April 24, 1913. l Serial No. 763,221.

to be understood that the invention is not limited to the detailed construction therein shown, but that the same may be varied within the scope of the appended claims.

In the said drawings:

Vso

Figure 1 is a longitudinal section of a pump yembodying my invention; l

Fig. 2 is an end view from the left of the mechanism shown in Fig. 1.

Figs. 3, 4y and 5 are transverse sectionsl on the correspondingly numbered lines of Fig. 1; and

Fig. 6 is a detail View of the balancingv mechanism. y

Referring-now to the drawings in which like characters represent like parts in the different views, 1 indicates the driving shaft of the -pump which projects through a suitable stuiiiing box in the end of the shaft casing 2. Within the casing"the shaft is about twicey the diameter of its projecting end and is rotatably supported in suitable bearings 3, 3' at each end of the casing' 2. A suitable double thrust bearing comprising collars 4 and 5 attached to the shaft and spaced apart to receive a xed ring 12 at-vtached by suitable bolts to the shaft casing 2, is provided at the end of the enlarged portion of the shaft for holding the shaft against longitudinal. movement from the reaction of the driving and adjusting forces as A will be hereinafter described. A

The inner end of the enlarged portion of the shaft 1 projectsthrough the inner bearing 3 and terminates in an annular flange 13 spaced a short distance from the bearing.

Attached to the casing 2 is the crank lchamber 14 for the pump cylinders, 15, here shown as five in number and radially arranged around the axial center of the driving shaft 1. On the opposite side of the cylinders 'l5 a bearing 16 is provided similar to the bearing 3, and beyond the bearing 16 is the crank chamber 17 for the radial valve chambers 18. O n the opposite side of the chamber 17 is a bearing 16 similar t0 the bearing 16 and mounted inthe bearings 16, 16', is a shaft 19 similar to the :enlarged portion of theshaft 1 and likewise terminating in a iange 13', within the crank chamber 14. The shafts 1 and 19 are each provided with a longitudinal bore 20 preferably rectangular as shown more particularly in Figs. 3 and 4, these bores being offset or eccentric to the center of rotation of the shaft sections. Slidably mounted in the bores 20 is a shaft section 21 fitting the bores 20 and having its middle portion 22 inclined relative to its two end portions whereby the two end portions are offset from each other a distance equal to the sum of the eccentricities of the two bores 20, so that when the parts are assembled with the shaft sections 1 and 19 positioned with their bores on opposite sides of the center of rotation the ends of the shaft 21 will be free to move longitudinally to the extent permitted by the bores 2O which are enlarged at 20 for the purpose. Mounted on the inclined portion 22 of the shaft 21 is a sleeve 23 of a nwidth suflicient to just lit between the two flanges 13, 13 of the shafts 1 and 19 so as to be held against longitudinal movement and thereby be moved radially by the longitudinal adjustment of the shaft 21 as will be readily understood. The outer cylindrical surface of the sleeve 23 is parallel with the axis of rotation and forms the effective crank pin of the pump to which the pistons are operatably connected in any approved manner.l y

In the drawings I have shown the sleeve 23 as surrounded by the inner member of a roller bearing 24 against whose ring 25 the curved shoes 26 forming the inner ends of the connecting rods of the pistons 27 are held in operative relation by the usual retaining rings 25. As will be understood, when the shaft 21 is so adjusted that the middle point of its inclined ortion 22 is in line with the median line o the cylinders, the outer periphery of the sleeve 23 will be concentric with the center of rotation, and when the shaft 21 is shifted in either direction from such central position the sleeve 23 will be laterally displaced a distance depending upon the extent of longitudinal movement of the shaft 21 and will form an operating crank pin on a throw eq'ual to the distance of the center of the sleeve from the center of rotation.

When the sleeve 23 and its conn'ectedvpartsY are in their concentric or zero position their mass is obviously equally distributed around the center of rotation and the parts are therefore ,.balaneed, but when the sleeve is laterally shifted the center of gravity of its parts no longer coincides with the center of rotation and must thereforebe counterbalanced to avoid the excessive strains and vibration incidental to the rapid rotation of the shaft. v For this purpose I provide the counterbalancing mechanism shown more particularly in Figs. 4, 5 and 6. On each of the shaft' sections 1 and 19 between!A the flanges 13, 13 and the adjacent bearings 3 and 16, I pivotally mount two counterweights 28 and 29 and 28 and 29 respectively, all of which are substantially identical in construction and comprise a ring-like hub encircling the shaft sections and a sector shaped Weight portion 30 of substantially 90 degrees extent and provided in its face adjacent the sleeve 23 with middle radial slot 31. The sleeve 23 is slightly Wider than the bearing 24 and is reduced at its ends to form bearings for cam levers 32, one for each weight at each end of the sleeve. These levers are identical and are of the shape shown more particularly in Fig. 5 comprising a rounded extension fitting in the slots 31 of the counterweights and an enlarged body portion 33 whose cuter periphery forms the cam surface and operatively engages two opposite rollers 34, mounted upon pins projecting from the inner faces of the flanges 13, 13 of the shaft sections. It will be understood that each of the counterweights has its separate cam lever 32 and that each cam lever has its separate pair of co-acting rollers. The cam portions 33 are so shaped that when the sleeve 23 is concentric with the center of rotation the eX- tremities of the cam levers will extend in .diametrically opposite directions in a line transverse to the line of movement of the sleeve 23 and as the counterweights and their actuating parts are equal in weight they will balance each other and will not affect the balanced condition of the adjustable crank mechanism at this position. When the sleeve 23 is laterally adjusted in either direction the cam levers act as levers of the first class working between the rollers as a shifting fulcrum and operating to adjust the' counterweights in opposite directions to bring them toward each other on the side of the shaft opposite to the sleeve 23. As the counterweights are identical in weight and are equally shifted the center of gravity of their combined mass will always lie in the diametric extension of the' line of the lateral movement-of the center of thesleeve 23, and by properly shaping the peripheries of their cam portions, the extent of their movement upon any lateral movement of the sleeve 23 willbe such"that their balancing force will be equal and opposite to the unbalanced force of the sleeve 23 and its associated parts.

For adjusting the shaft section 21 longitudinally of the shafts 1 and 19 I provide a power operated adjusting mechanism by means of which power derived from the driving shaft will adjusty the shaft 21 a distance corresponding to the distance and direetion which the manually actuated member is adjusted. To this end, the end of the shaft 21 which extends into the shaft 1 is provided with a transverse pin 40 projecting through slots 41 on opposite sides of the shaft 1 of sufficient length to permit the desired longitudinal movement of the shaft section 2,1. Slidably mounted on the exterior of the shaft 1 is a ring 42 in which'are seated the ends of the pin 40. The ring 42 is provided at each end with' collars 42 between which is rotatably mounted a ring 43 ixedly clamped between two parts of a sectional ring 43. The sections of the ring 43 are provided on opposite sides with ears 43 forming in effect slots for the reception of pins 44 fixed in the arms of a yoke 45 which embraces the ring 43. The yoke 45 .is pivotally suspended from a transverse 15, and

shaft 46, mounted in the casing 2 above the shaft 1 midway between the bearings 3 and 3. The ends of the arms of the yoke on the under side of the'shaft 1 are provided with pins 47 which engage slots in the opposite sides of a nut 48 guided for longitudinal movement by suitable ribs on the bottom of the casing 2. The nut 48 is threaded on a longitudinalv shaft 49 rotatably mounted in the casing beneath the shaft 1 in suitable bearings 50, 51. The shaft 49 projects beyond the bearing 50 and slidably mounted on its projecting end is a double cone-faced clutch member 52.- Adjacent the bearing 50 the casing 2 is provided with a journal box 54 within which is rotatably mounted the hub of a .gear wheel 55 driven from a gear 6 onthe shaft 1 and having its inner face shaped to coperate with one clutch face of the clutch member 52. The end cap 56 of the casing 2 is formed with asimilar journal box 57 in which is rotatably mounted a gear 58 driven in a direction opposite to the gear 55 by the gear 6 and an idler 7 and having an inner conical face for coperating with the op osite face of the member 52.

The clutc member 52 beyond the shaft 49 terminates in a suitable spool with which is rotatably engaged an actuating arm 59, eX- tending transversely of themachine and provided at each end with a pivotally connected longitudinal rod 60 which extends parallel with the screw shaft 49. The rods 60 terminate about midway betweenv the bearings of the shaft 49, and to the end of each there is pivotally connected a lever arm 61 fulcrumed at its middle point on the reduced projecting end of the pins 44'by which the yoke 45 engages the adjustlng rlng. The ends of the levers 61 project above the yoke 45 and are slotted for the greater part of their length for the reception of pins 62 in theends of arms 62 attached to the shaft 46 on which the yoke 45 is pivotally supported. The shaft 46 projects through the casing and to its projecting end there is attached a lever 62 by which the arms 62 maybe manually operated. j, j

The valve chambers 18 are each provided with a middle port connected by suitable passage way with the ends of the cylinders are also provided with outer and 1nner ports 63 and 64 connected by suitable manifolds 63', 64 to which the corresponding orts of the motor` element of the transmission are to be connected in a manner which will be readily understood from my prior patent above referred to. Each of the valve chambers is provided with a reciprocatn valve 65 having a middle head adapted w en the valve is midway of its stroke to exactly close the port from the pump cylinder, and when moved in either dlrection therefrom to connect the pump cylinder with either the outer or inner ort 63 or 64. For actuating the valves 65 provide an eccentric 66 attached to the shaft section 19 in a position such that its line of greatest throw is at right angles to the crank arm of the pump shaft when the ring 23 is adjusted out of its central or zero position. It is obvious that when the ring 23 is on one side of its zero position the crank arm of the valve operating eccentric will be either. 90 degrees in advance or 90 degrees behind the crank arm of the pump piston depending on the direction of rotation of the pump shaft, and when the ring 23 is adjusted through its zero position the position of its crank arm relative to that of the valve operating ec centric will be reversed, and consequently the direction of flow of the fluid and the direction of rotation of the motor will be reversed, as 'will be readily understood from my prior patent above referred to. i,

The operation of the device will now be described. Let it be assumed that the parts of the machine are in the positions shown in Fig. 1 of the drawings, that the ring 23` is concentric with the axial line of the shafts 1 and 19 and the shaft 1 is driven from a suitable source and rotating to the left, i. e. in a counterclockwise direction.l Rotation of the shaft will obviously not eifect the reciprocation of the pump pistons and consequently no fluid under pressure will be delivered by the pump to the motor. If the operator wlshesto drive the motor 'shaft in say the same direction as that of the driving shaft he will move the lever 62 to the left as shown in Fig. 1 thereby through the arms 62 leverV arms 61 and rods 60 moving the clutch member 52 into engagement with the gear 58 to rotate the shaft 49 in a counterclockwise direction and shift the nut y4,8 with which the ends of the yoke 45 are engaged to the right. The yoke being fulcrumed above the shaft 1 and engaging the ring 43 at the middle points of its arms, the ring also will be shifted to the right thereby adjusting the square shaft section 21 to the right and shifting the ring 23 out of its los tionary the lever arms 61 will be turned on` the pins 62 as fulcra thereby shifting the clutch 52 out of engagement with the gear 58, stopping the rotation of the screw shaft and the adjustment of the shaft section. If the operator wishes the adjustment to be continuous throughout the change in the stroke he continues the movement of the operating lever 62. at a speed to compensate for the movement of the yoke 45 so that the arms 61 turn on their connections with the rods 60 as fulcra and thereby do not disengage the clutch. As soon as the operating lever reaches the point which indicates that the pump stroke has been adjusted to the desired extent the operator has merely to hold the lever stationary a moment in order for the slight continued movement of the yoke to disengage the clutch. To adjust the yoke in the opposite direction to that just described to thereby reduce the speed of the motor or reverse its direction, the operator has merely to shift the lever` 62 in the opposite direction thereby bringing the clutch 52 into engagement with the gear 55 which is driven in a clockwise direction by direct enga ement with the gear 6. The reverse rotation of the shaft 49 will obviously cause the nut 48 to travel in the Aopposite direction shifting the yoke and shaft section 21 to the left and returningv the sleeve 23 toward its zero position. If the adjustment be continued through a sulicient distance the sleeve 23 will be adjusted through its position of concentricity, thereby giving the 'effect of an operative crank arm 180 degrees distant angularly from its crank arm in the first described position. As explained above this change in relation of the crank arm and the valve crank arm reverses the direction of the flow of Huid and consequently the direction of rotation of the motor.

The lateral adjustment of the sleeve 23 acts through the operating arms 32 to shift the counterweights angularly toward or from each other to thereby vary their counterbalancing effect in the manner described. The adjusting mechanism described is simple and positive in its operation and always adjusts the stroke of the pump to an extent exactly corresponding with the movement of. the operators lever. Further as long as the lever is continued in one position any accidental displacement o f the shaft 21 from a position corresponding to that of the lever will be immediately automatically corrected, for the reason that for each position of the lever there is but one corresponding position for the yoke and ring, and any movement thereof from its position will bringthe clutch member into engagement with one or the other of the gears 55 or 58 to return the yoke to its position corresponding with the operators lever. The screw 49 is'irreversible so that the mechanism will always said rotatable section,

adjustable by the movement of said last be retained in the position to which it is adjusted.

Variable stroke crank shafts of the type shown are necessarily larger at the crank pin than ordinary crank shafts for transmitting the same amount of power, and 1t is therefore all the more important to balance them, especially where they operate at moderate or high speeds.

What I claim is,

1. In a variable stroke pump, the combination of a cylinder, a piston therein, a crank for reciprocating said piston comprising a crank pin adjustable in a radial line, and means for balancing the centrifugal moment of said crank pin in different positions of adjustment thereof.

2. In a variable capacity pump, the combination of a cylinder, a piston therefor, a crank shaft for operating said piston having a crank pin adjustable in a radial line, and means for balancing the centrifugal moment of said crank pin in different positions of adjustment comprising a rotatably adjustable counterweight.

3. In a variable capacity pump, the combination of a cylinder, a piston therefor, a crank shaft for operating said piston having a crank pin adjustable in a radial line, means for vbalancing the centrifugal moment of said crank pin in different positions of adjustment comprising a rotatably adjustable counterweight, and connections between said crank pin and counterweight whereby the adjustment of said crank pin effects the proportionate movement of said counterweight.

4. In a'mechanism of the class described, a variable stroke crank shaft comprisin an axially slidable part, a crank pin radlally adjustable by the axial movement of said part, and a movable counterweight for said crank pin adjustable by the movement of said crank pin to balance the .centrifugal moment of said crank pin in different positions of adjustment.

5. In a mechanism of a variable stroke crank shaft comprising an axially slidable part, a crank pin radially adjustable by the axial movement of said part, a movable counterweight for said the class described,

'crank pin adjustable by the movement of ksaid crankpin to balance the centrifugal moment of said crank pin in different positions of adjustment, and power operated means driven from said crank shaft for adjusting said axially ,movable part.

In a mechanism of the class described, a variable stroke crank shaft comprising a shaft section rotatable in ixed bearings, a shaft section longitudinally adjustable in named section, and means for adjusting said last named section comprising a sleeve slida crank pin radially slidable part, and means ingly mounted on said rotatable shaft section and fixed to said adjustable shaft section, a power operated member operatably con'- nected thereto, a manually operatable member, and connections between said last named member 'and said power operated member for causing the movement of said power` operated member to be in synchronism with the movement of said manually operatable member.

7. In a mechanism of the class described, a variable stroke crank shaft having a longitudinally adjustable part, means for adjusting the same comprising a screw shaft, a nut on said shaft operatably connected with said part, connections between said screw shaft and said crank shaft for driving said screw shaft in opposite directions, and means for controlling said connections comprising a shiftable member for making and breaking the connection between the screw shaft and the crank shaft, a manually operatable member and a floating lever, connected to said manually operatable member, to said adjustable shaft part and to said shiftable member.

8. In a mechanism of the class described, a variable stroke crank shaft having a longitudinally adjustable part, means for adjusting the same comprising a screw shaft, a nut on said shaft operatably connected with said part, and connections between said screw shaft and said crank shaft for driving said screw shaft in opposite directions, said means comprising a plurality of clutches, and a controlling mechanismD for said clutches comprising a manually operatable member and a floating lever connected to said member, to said adjustable shaft part and to said shiftable clutch.

9. In a mechanism of the class described, a variable stroke crank shaft comprising a part rotatable in fixed bearings, an axially slidable part carried'thereby, a crank pin radially adjustable by the movement of said for balancing said crank pin comprising a counterweight rotatably mounted on said rotatable shaft section and operatably connected with said crank pin for rotary adjustment in proportion to the radial adjustment of said crank pin.

10. In a mechanism of the class described, a crank shaft comprising a radially adjustable crank pin, a pl rality justable counterweights for balancing said crank pin, and connections between said weights yand said crank pin for effecting equal and opposite adjustments of said counterweights upon the adjustment of said crank pin.

of radially ad- 11. In a variable stroke pump, the combination of a cylinder, a piston therein, a crank shaft for reciprocating said piston comprising a shaft element, a crank pin element radially adjustable in a straight line with respect to said shaft element, means for adjusting said crank pin element and means for balancing the centrifugal force. of said crank pin element in different positions of adjustment comprising a balance weight circumferentially adjustable with respect to said shaft element.

12. In a variable stroke pump, the combination of a cylinder, a piston therein, a crank shaft for reciprocating said piston comprising a driving shaft element, a crank pin element radially adjustable in a straight line with respect to said shaft element, means for adjusting said crank pin element and means operated by said crank pin element adjusting means for balancing the centrifugal force of said crank pin element in diEerent positions of adjustment comprising a balance weight circumferentially adjustable with respect to said shaft element.

13. In avariable stroke pump, the combination of a cylinder, a piston therein, a

.crank shaft for reciprocating said piston comprising a crank pin element, shaft elements supporting said crank pin element at each end thereof and said crank pin element is radially adjustable, means for adjusting said crank pin element, and means for balancing'the centrifugal force of said crank pin element in different positions of adjustment comprising a balance weight circumferentially adjustable with respect to said shaft element.

14. In a variable stroke pump, the combination of a cylinder, a piston therein, a crank shaft for reciprocating said piston comprising a .crank pin element, shaft elements supporting said crank pin element at each end thereof and with respect to which said crank pin element is radially adjustwith respect to which able, means for adjusting said crank pm 

